AuthorTopic: Canvas Prints short on 7890 (Read 8459 times)

I am stumped !! When I print on Canvas my prints come out short on the 7890...The width is as specified. The length is also inconsistent from print to print. For example I want a print 15" long...I will have to specify 15.5 " in photoshop. Some prints will be 15" some might be 15.125 some 14.75.? There is a margin width of 2" for trimming and wrapping so it is not being cut because of too little margin space.

There are lots of threads here on this subject (do a search), but it boils down to the fact that canvas shrinks on the "long" side. Different canvases shrink at different rates. (Cotton shrinks.) The amount of ink laid onto each type of canvas also makes a difference... measurable, but slight (thankfully). Run a test with a measured image. I did it with a 8" x 36" test strip for each of the three canvas varieties I was using (wastes a lot of canvas and some ink, but saves money in the long run). Then use your Epson software's "Paper Feed Adjustment" to... adjust.

I don't really get why it would shrink a full. 5 inches on a 15" length and nothing on a 10" width, but it is very helpful to know that it is not a correctable software , driver problem, or operator error. I make my own stretchers so I will just "shrink" them accordingly.

There are lots of threads here on this subject (do a search), but it boils down to the fact that canvas shrinks on the "long" side. Different canvases shrink at different rates. (Cotton shrinks.) The amount of ink laid onto each type of canvas also makes a difference... measurable, but slight (thankfully). Run a test with a measured image. I did it with a 8" x 36" test strip for each of the three canvas varieties I was using (wastes a lot of canvas and some ink, but saves money in the long run). Then use your Epson software's "Paper Feed Adjustment" to... adjust.

Ken,Yes canvas shrinks but I still think we are talking 2 separate issues.I still fight this problem even after all the canvas I have worked with.Set up for a 23 x 23" print and get 23 x 22 5/8".Is it really possible that laying down ink could cause a print to shrink 3/8" 1 minute after printing?Sometimes it is right on and other times I get a funky length. Which brings up the question about shrinking or just printing the wrong sized image.Still no rime or reason.

Explain why you think changing the paper feed would help. All it says about using that is to correct banding.

That's right, the paper feed is for correcting banding. Banding occurs when the lines of ink/pigment are laid down too far apart (light band), or overlapping (dark band). As each line of wet ink is applied, the canvas shrinks (mostly on the long "warp" side, but also to some extent on the short "weft" side). The printer software tells the advance mechanism to roll a little further than "normal" to compensate for the subsequent line of ink and the expected shrinkage, just as you would have it correct for dark banding.

I don't understand why the printer manufacturers don't develop software that will automatically compensate. The software already knows how much of each ink the printer will spray. The canvas manufacturers, I presume, know how much each of their various canvases shrink, at least from plain water. The ink makers know how much water and other ingredients are in each color. That could work out to a simple scale of 1 to 10 that we users could type-in to the printer software. It might not always be spot-on, given the heat, humidity and other variables, but it sure would be a lot better than nothing at all.

Exactly why I cut my strecher frames after measuring my prints. Nominal is close enough.Where it can be a problem is when printing for someone that does their own gallery wraps. They already have purchased their fixed sized frames and the print comes to them almost a half inch off.I have a work around adding the 3/8" back on but it is still a major pain.

Your all thinking that the canvas is shrinking as its being printed? I'm having a hard time seeing that happening. I always thought it was the weight of the canvas that had the printer not really pulling it through as effectively as it can pull through a lightweight paper. Hence 'fooling' the printer and causing an inaccurate ending length. Not saying this is correct but shrinking as its printing?

Explain why you think changing the paper feed would help. All it says about using that is to correct banding.

I'm using Epson Exhibition Canvas on a 9800 and the instructions from Epson says to set paper feed to +70 , when I did that the prints came out to the exact size, when I don't do that they print short!

Epson recommends that same +70 setting for the 9880 9900 as well as for the 7800 series.. I still say give it a try cuz it works great.

I too have noticed this with my Canon iPF6100 and Canon Fine Art Water Resistant Canvas. To fix it, I just changed the size of the image in photoshop. So if I'm doing a Canvas that will end up being 60x20, hence my print is 64x24 with 2 inches all around for stretching, I just change the image size to be 64.25 and make sure my "constrain proportions" is unchecked. I also would create a paper size to be 64.25x24 and I pretty much get a print this side.

But here is the thing. When it comes to stretching, the print now ends up being too long. If you are just wrapping around, no problem, but but for a mirrored edge or just a black edge, you want to make sure that your "seams" so to speak line up. And after you stretch your canvas, (i make mine pretty tight), the 64.25 ends up being too long. So now I just print 64x24 as is, and even though it is a little shorter on the long end, once I stretch with my canvas pliers, it stretches back out quite nicely and ends up being within 1 or 2mm exactly where the edge of the stretcher bar is. Hope this helps.

Your all thinking that the canvas is shrinking as its being printed? I'm having a hard time seeing that happening. I always thought it was the weight of the canvas that had the printer not really pulling it through as effectively as it can pull through a lightweight paper. Hence 'fooling' the printer and causing an inaccurate ending length. Not saying this is correct but shrinking as its printing?

I'm with you on this. I don't think that the canvas shrinks at all. Here's a way to test it (which I will do sometime soon and report back): spool out a substantial amount of canvas, say 60cm. Make a mark at the cut edge and another mark as far back down the canvas you can go. record the exact distance between the marks. Spool the canvas back and then print an image between these two marks. If the canvas shrinks then these two marks will move closer together, not so?

Also: just used the +70 paper feed adjustment for printing BC Lyve on a 9900. Output size matched input size exactly, print was about 32" long. Media type set to WC Radiant White as per BC suggestion.

I'm with you on this. I don't think that the canvas shrinks at all. Here's a way to test it (which I will do sometime soon and report back): spool out a substantial amount of canvas, say 60cm. Make a mark at the cut edge and another mark as far back down the canvas you can go. record the exact distance between the marks. Spool the canvas back and then print an image between these two marks. If the canvas shrinks then these two marks will move closer together, not so?

Suppose some canvas qualities are tightly wound on the core, would your test still be valid?

Suppose some canvas qualities are tightly wound on the core, would your test still be valid?

Good thinking. Yes and no. It would test for shrinkage due to wetting. It would not test for shrinkage that occurs as a tightly wound canvas is unwound.

In my little world I use BC Lyve, which is polycotton, and is not tightly wound. I have not done my test yet, but I suspect that it has no shrinkage as it is used. I'm getting accurate output sizes. I accept that other canvases are manufactured and wound differently and that they might shrink due to wetting or winding.

If I was being very fussy I would run the test at the beginning, middle and end of a roll to see if/how things change as the roll is used up.